Method of making coated article having antibacterial and/or antifungal coating and resulting product

ABSTRACT

Techniques are provided for making a coated article including an antibacterial and/or antifungal coating. In certain example embodiments, the method includes providing a first sputtering target including Zr; providing a second sputtering target including Zn; and co-sputtering from at least the first and second sputtering targets in the presence of nitrogen to form a layer including ZnxZryNz on a glass substrate. These layers may be heat-treated or thermally tempered to form a single layer including ZnxZryOz. In other examples, two discrete layers of Zn and Zr may be formed. The coating may be heated or tempered to form a single layer including ZnxZryOz. Coated articles made using these methods may have antibacterial and/or antifungal properties.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a divisional of application Ser. No. 13/271,828filed Oct. 12, 2011, which is a continuation-in-part of application Ser.No. 12/662,443 filed on Apr. 16, 2010, the entire contents of each ofwhich are hereby incorporated by reference in this application.

Certain example embodiments of this invention relate to a method ofmaking a coated article having an antifungal/antibacterial coatingsupported by a substrate, and the resulting coated article product.Coated articles according to certain example embodiments of thisinvention may be used for windows, table tops, picture frame covers,furniture glass, and/or the like.

BACKGROUND AND SUMMARY OF EXAMPLE EMBODIMENTS OF THE INVENTION

Vehicle windows (e.g., windshields, backlites, sunroofs, and sidelites)are known in the art. For purposes of example, vehicle windshieldstypically include a pair of bent glass substrates laminated together viaa polymer interlayer such as polyvinyl butyral (PVB).

Insulating glass (IG) windows are also known in the art. Conventional IGwindow units include at least first and second glass substrates (one ofwhich may have a solar control coating on an interior surface thereof)that are coupled to one another via at least one seal(s) or spacer(s).The resulting space or gap between the glass substrates may or may notbe filled with gas and/or evacuated to a low pressure in differentinstances. Many IG units are tempered. Thermal tempering of the glasssubstrates for such IG units typically requires heating the glasssubstrates to temperature(s) of at least about 580 degrees C. for asufficient period of time to enable thermal tempering. Monolithicarchitectural windows for use in homes or building are also known in theart. Fixture windows in homes such as shower stall windows may be madeof glass sheets. Again, monolithic windows are often thermally temperedfor safety purposes.

Other types of coated articles also are sometimes subjected to heattreatment (HT) (e.g., tempering, heat bending, and/or heatstrengthening) in certain applications. For example and withoutlimitation, glass table tops, picture frame covers, and the like may besubject to HT in certain instances.

Germs are becoming of increasing concern across the world, especially inview of the large amount of international travel taking place in today'ssociety. There exists a need in the art for coated articles for use inwindows, table tops, and/or the like that are capable of killing germs,viruses, and/or bacteria, thereby reducing the likelihood of personsbecoming sick. It also would be advantageous if such characteristics ofa coated article could be combined with scratch resistant features.

It will be appreciated that there exists a need in the art for a coatedarticle (e.g., for use in a window, shower door, and/or table-top glass)having antifungal and/or antibacterial properties. It also may also bedesirable for the coated article to have scratch resistance properties.Furthermore, it would be desirable to provide a coated article that isboth scratch resistant and can function to kill certain bacteria and/orfungus which come into contact with the coated article thereby reducingthe chances of persons becoming sick.

Certain example embodiments of this invention relate to a method ofmaking a coated article having antifungal/antibacterial properties,and/or the resulting product. In certain example non-limitingembodiments, there is provided a method of making a coated article(e.g., window such as for a vehicle or building, shower door window, buswindow, subway car window, table top, picture frame cover, or the like)that may be capable of being heat treated so that after being heattreated (HT) the coated article is scratch resistant to an extent morethan uncoated glass, as well as more resistant to bacterial and fungalgrowth than uncoated glass. The coated article may or may not be heattreated in different embodiments of this invention.

In certain example embodiments of this invention, ZrO₂ and ZnO areco-sputtered on a glass substrate to form a layer comprising zinczirconium oxide (e.g., Zn_(x)Zr_(y)O_(z)). The glass substrate may ormay not be provided with a barrier layer provided between the glasssubstrate and the layer comprising zinc zirconium oxide. For example andwithout limitation, the thin barrier layer may comprise silicon nitride,silicon oxide, and/or silicon oxynitride. The co-sputtered zinczirconium oxide based layer may be provided directly on the glasssubstrate, or on the glass substrate over other layer(s) such as thebarrier layer. While the substrate may be of glass in certain exampleembodiments of this invention, other materials such as quartz mayinstead be used for substrates in alternative embodiments. The coatedarticles described herein may or may not be thermally tempered and/orpatterned in certain example embodiments of this invention.Additionally, it will be appreciated that the word “on” as used herein(e.g., a layer “on” something) covers both direct and indirect contact,e.g., a layer “on” another layer with other layer(s) possibly beinglocated therebetween.

In certain example embodiments, there is provided a method of making acoated article, the method comprising: providing a first sputteringtarget comprising Zr; providing a second sputtering target comprisingZn; and co-sputtering at least the first and second sputtering targetsto form a layer comprising a nitride of Zr doped with Zn on a glasssubstrate, wherein the layer comprises from about 0.25% to 20% (atomic)Zn. The layer of or including the nitride of Zr doped with Zn may thenbe heat treated (e.g., thermally tempered), which causes the layer totransform into a layer comprising or based on zinc zirconium oxide(e.g., Zn_(x)Zr_(y)O_(z)).

In certain example embodiments, the zirconium oxide in the layercomprising zinc zirconium oxide is substantially crystalline, andamorphous zinc oxide is “hidden” in a zirconium oxide (e.g., ZrO₂)matrix, and, for example, can release gradually to the surface such thatthe coating has lasting antimicrobial properties. The zirconium oxide(e.g., ZrO₂) matrix may be cubic or substantially cubic, with itsstructure such that it permits zinc particles to migrate or diffusetherethrough to the exterior surface of the coating over long periods oftime. When the zinc particles reach the exterior surface of the coatedarticle in a substantially continuous manner over time, they function tokill at least some bacteria and/or fungi that may come into contact withthe zinc, or proximate the zinc, on the surface of the coated article.

In certain example embodiments, the zinc is protected from theenvironment by a porous layer(s) provided over the layer comprising zinczirconium oxide (e.g., Zn_(x)Zr_(y)O_(z)). In different exampleembodiments, the zinc zirconium oxide (e.g., Zn_(x)Zr_(y)O_(z))inclusive layer may comprise, consist essentially of or consist of Zn,Zr and O.

In order to achieve the structure desired in certain exampleembodiments, the zinc or zinc oxide can be “hidden” in a skeleton ormatrix of zirconium oxide. In order to “hide” the zinc or zinc oxide inthis manner, the coating can be co-sputtered (or sputtered from asingle, mixed target, in certain instances) in a controlled way asfollows.

In a first example embodiment, the zinc is sputtered from an angledtarget. More specifically, a Zr inclusive target is substantiallyperpendicular to the substrate, and a Zn inclusive target is offset fromnormal by an angle theta (θ). This position assists forming a layer withzinc or zinc oxide “hidden” in a zirconium oxide based matrix, and helpsmaintain the stability of the crystalline formation in the coating afteroptional heat-treatment. As used herein, “Zr target” includes a targetcomprising zirconium and/or zirconium oxide, and “Zn target” includes atarget comprising zinc and/or zinc oxide. In certain exampleembodiments, a Zr target may comprise or consist essentially of Zr, anda Zn target may comprise or consist essentially of Zn. There may besmall amounts of other elements included in each target.

In a second example embodiment, the coating is deposited via powercontrolled co-sputtering. In this embodiment, the Zr and Zn targets canbe substantially parallel or angled from each other, but are sputteredusing different amounts of power to control the composition andcrystallinity of the coating in a desirable manner.

In a third example embodiment, one target may comprise zirconium andzinc (and possibly oxides of one or both) in a ratio which operates tohelp control the composition and crystallinity of the coating. Forexample, the target may contain a patched or other pattern of zirconiumand zinc to ensure that each respective element is deposited in thedesired amount, and is in substantially crystalline form (or in aformation that is conducive to becoming crystalline upon heattreatment). The target may comprise any pattern that would create theappropriate ratio and structure when sputtered.

The deposition method of zirconium and/or zinc oxide(s) is not limitedto the above embodiments. Any other deposition method that would createand maintain a matrix of or based on Zn_(x)Zr_(y)O_(z), in theappropriate ratio, may be used. Moreover, the first, second and thirdembodiments may or may not be used in combination with each otherherein.

In certain example embodiments, co-sputtered zirconium and zinc oxidesresult in a zinc zirconium oxide-inclusive layer that exhibits excellentscratch resistance, combined with antibacterial and/or antifungalproperties. It can reduce the likelihood of visible scratching up to a20 pound load when abraded with a ⅛ inch borosilicate sphere, so thatthe product is more scratch resistant than is a similar product absentthe coating.

In certain example embodiments of this invention, a method of making acoated article is provided. A first sputtering target comprising Zn, anda second sputtering target comprising Zr are provided. A first discretelayer comprising Zn is formed on a glass substrate via the firstsputtering target. A second discrete layer comprising Zr is formed overand contacting the layer comprising Zn. The first and second discretelayers are heat treated (e.g., together at substantially the same time)to produce a single layer comprising Zn_(x)Zr_(y)O_(z).

In certain example embodiments of this invention, a method of making acoated article is provided. A first sputtering target comprising Zr anda second sputtering target comprising Zn are provided. At least thefirst and second sputtering targets are co-sputtered in the presence ofnitrogen to form a layer comprising Zn_(x)Zr_(y)N_(z) on a glasssubstrate. The layer comprising Zn_(x)Zr_(y)N_(z) is heat treatable suchthat, when heat treated, the layer comprising Zn_(x)Zr_(y)N_(z) forms alayer comprising Zn_(x)Zr_(y)O_(z) having antimicrobial and/orantifungal properties.

In certain example embodiments of this invention, a method of making acoated article is provided. A first sputtering target comprising Zn, anda second sputtering target comprising Zr are provided. Sequentiallysputtering is performed from at least the first and second sputteringtargets onto a glass substrate to form at least a first layer comprisingZn having a thickness of from about 20 to 50 Å, and a second layercomprising Zr located directly on the first layer comprising Zn andhaving a thickness of from about 100 to 250 Å. The Zr is sputtered inthe presence of nitrogen. The glass substrate is heat treatable withsaid first and second layers thereon to form a layer comprising zinczirconium oxide with antibacterial and/or antifungal properties on thecoated article.

In certain example embodiments of this invention, there is provided amethod of making a coated article comprising a glass substratesupporting a coating. The coating is sputter deposited on the substrate,with the coating comprising an anti-microbial material located within acarrier material. The anti-microbial material comprises Zn, Ag, and/orCu. The carrier material comprises Zr, Si, Ti, Hf, and/or Al. Thesputter depositing is practiced by either (a) co-sputtering from two ormore targets, or (b) sputtering from a mixed metal target.

These features, aspects, advantages, and example embodiments may be usedseparately and/or applied in various combinations to achieve yet furtherembodiments of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages may be better and morecompletely understood by reference to the following detailed descriptionof exemplary illustrative embodiments in conjunction with the drawings,of which:

FIG. 1 is a cross-sectional view of an antimicrobial coating accordingto an example embodiment of this invention.

FIG. 2 is a table comparing antimicrobial properties of co-sputteredzinc zirconium oxide to those of silver, a conventional antimicrobialcoating material, and uncoated glass, according to an example embodimentof this invention.

FIG. 3 is an XPS depth profile graph of an example composition of a zinczirconium oxide-inclusive layer according to an example embodiment ofthis invention.

FIG. 4 is an XRD of the crystallinity of an example zinc zirconiumoxide-based layer after heat treatment/thermal tempering according to anexample embodiment of this invention.

FIG. 5 shows an angled Zn target according to an example embodiment ofthis invention.

FIG. 6 shows power-controlled co-sputtering from both Zn and Zr targetsaccording to another example embodiment of this invention.

FIG. 7 shows sputtering zinc and zirconium from a single, patchedtarget, according to another example embodiment of this invention.

FIGS. 8a, 8b, and 8c show an example of sequential sputtering, accordingto yet another example embodiment.

FIG. 9 illustrates a scenario in which Zn- and Zr-inclusive layers areinitially formed discretely, but ultimately result in a combined singlelayer after heat treatment in accordance with certain exampleembodiments.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

In certain example embodiments of this invention, ZrO₂ and ZnO areco-sputtered on a glass substrate 1 to form a layer comprising zinczirconium oxide 3 which can be the outermost layer of a coated article.The glass substrate may or may not be provided with a barrier layer 2thereon, with the barrier layer being optionally located between theglass substrate 1 and the layer antibacterial and/or antimicrobial layercomprising zinc zirconium oxide 3. For example and without limitation,this thin barrier layer 2 may comprise silicon nitride, silicon oxide,and/or silicon oxynitride in example embodiments. The co-sputtered zinczirconium oxide-based layer 3 may be provided directly on the glasssubstrate 1, or on the glass substrate 1 over other layer(s) such as thebarrier layer 2. While the substrate 1 may be of glass in certainexample embodiments of this invention, other materials such as quartz,plastics, and/or the like may instead be used for substrates inalternative embodiments. The coated article described herein may or maynot be thermally tempered and/or patterned in certain exampleembodiments of this invention.

Silver is a known antibacterial agent. However, its antifungalproperties are not necessarily as desirable as some other materials. Forexample, compared to silver, ZrO₂/ZnO (e.g., forming aZn_(x)Zr_(y)O_(z)-based layer) according to certain example embodimentsof this invention can possess comparable antibacterial properties andgood antifungal properties. Thus, improved antifungal properties may beprovided in certain example embodiments of this invention.

In certain example embodiments, the layer 3 may originally be depositedas of or including Zn—ZrN, which is zirconium nitride doped with Zn. Forexample, the zirconium nitride can be doped with from about 0.25% Zn,more preferably from about 0.25% to 15% Zn, more preferably from about1-15% Zn, more preferably from about 1-10% or 1-5% Zn. Then, when theglass substrate 1 supporting the Zn—ZrN coating is thermally tempered(e.g., heat treated at temperatures of at least about 580 degrees C., ormore preferably at least about 600 degrees C.), the Zn—ZrN wouldtransform into Zn—ZrO₂ or possibly another form of zirconium oxide dopedwith the same amounts of Zn discussed above. In certain exampleembodiments, a layer comprising Zn—ZrN and/or ZnZrNx may advantageouslyhave an improved mechanical and/or chemical durability prior to heating.In further examples, the tempering window (e.g., temperature and/orduration, etc.) may be wider, with respect to the absence/reduction ofvisible haze.

In certain example embodiments, when heated, a layer comprising Zn—ZrNand/or ZnZrNx may also result in formation of a Zn_(x)Zr_(y)O_(z)-basedlayer 3 according to example embodiments of this invention. Of course,the layer 3 may originally be deposed as Zn_(x)Zr_(y)O_(z) or Zn—ZrO₂ incertain example embodiments of this invention.

There are two major industrial standards for testing antimicrobialproperties of an article. The tests are the JIS Z 2801 test (which testsantibacterial properties), and the ASTM G21test (which tests antifungalproperties). The JIS Z 2801 test uses a value referred to as “R” toevaluate the antibacterial properties of the material being tested. TheR value of the surface or article being tested is the log of the ratioof microbe concentration(s) on coated and uncoated products. For example(and without limitation), if R=2, this means that the microbeconcentration at the end of the test is 100.times. less on the coatedproduct than on the uncoated product. R=2 and higher is defined asbiocidal. In an ASTM G21 test, the fungal growth is rated from 0-4. 0 isdefined as substantially no fungal growth, 1 is defined as traces ofgrowth (less than 10%), 2 is defined as light growth (10-30%), 3 isdefined as medium growth (30-60%), and 4 is defined as heavy growth (60%to complete coverage).

An antimicrobial and/or antibacterial layer comprising zinc zirconiumoxide 3 according to certain example embodiments is surprisinglyadvantageous, in that it has been found that the layer can kill at leastabout 80%, more preferably at least about 90%, and most preferably atleast about 99.99% E. coli (R=5.31), and at least about 80%, morepreferably at least about 90%, and most preferably at least about 99.94%S. Aureusi (R=3.23) in a JIS test. Moreover, in an antifungal (ASTM)test, it shows substantially no growth. The rating of aZn_(x)Zr_(y)O_(z) based layer 3 made according to certain exampleembodiments is substantially 0. This surprising and advantageous resultindicates that the zinc zirconium oxide-inclusive layer 3 allowssubstantially no fungal growth, as opposed to materials such as silver,which earn between 1 and 2 on the ASTM scale (up to 30% growth). Table 1compares the antifungal and antimicrobial properties ofZn_(x)Zr_(y)O_(z) based layer 3 to those of silver and glass.

TABLE 1 Antibacterial (JIS) E. Coli S. Aureusi Antifungal SampleReduction % R Reduction % R (ASTM) Clear Glass 0 0 0 4 Silver >99.996.22 >99.99 3.50 1-2 Average of >99.99 5.31 99.94 3.23 0 ZnZrOxZnZrOx/glass 99.99 5.01 0 ZnZrOx/SiNx 99.89 2.95 0 ZnZrOx/ZrO2 >99.996.22 99.99 3.90 ZnZrOx/SnOx 99.95 3.30 0

In certain example embodiments, the zinc in the Zn_(x)Zr_(y)O_(z) basedlayer 3 is protected from the environment by a porous layer(s) providedover the zinc zirconium oxide-based layer. Also, in certain exampleembodiments, a thin barrier layer 2 such as silicon nitride, siliconoxide, and/or silicon oxynitride may be provided underneath the zinczirconium oxide-based layer 3 to reduce and sometimes even preventalkali migration from the glass substrate 1 into the coating duringoptional heat treatment.

In certain example embodiments, zirconium oxide in the layer 3 iscrystalline, and amorphous zinc oxide is “hidden” in a zirconium oxide(e.g., ZrO₂) matrix in layer 3, and, for example, can release graduallyto the exterior surface of layer 3 such that the coating has lastingantimicrobial properties. The zirconium oxide (e.g., ZrO₂) matrix may becubic or substantially cubic, with its structure such that it permitszinc particles to migrate or diffuse therethrough to the exteriorsurface of the layer 3 over periods of time. When the zinc particlesreach the surface of the coated article in a substantially continuousmanner over time, they function to kill at least some bacteria and/orfungi that may come into contact with the zinc, or proximate the zinc,on the surface of the coated article.

In order to “hide” the zinc oxide in this manner, the zinc zirconiumoxide-based layer 3 may be co-sputtered (or sputtered from a mixed,single target, in different instances) in a controlled way according tocertain example embodiments. As used herein, “co-sputtered” may refer tosubstantially simultaneous sputtering from at least two targets.

The sputtering target(s) discussed below in the example embodiments canbe planar target(s), rotating cylindrical magnetron target(s), or acombination thereof. Metal or ceramic targets may be used.

In a first example embodiment, the zinc is sputtered from an angledtarget. An example of this is shown in FIG. 5. More specifically, the Zrtarget is substantially perpendicular to the substrate, and the Zntarget is offset by an angle of theta (θ), as shown in FIG. 5. Thisposition assists informing a layer 3 with zinc oxide “hidden” in azirconium oxide matrix, and helps maintain the stability of thecrystalline formation in the coating after optional heat-treatment. Asused herein, “Zr target” includes a target comprising zirconium and/orzirconium oxide, and “Zn target” includes a target comprising zincand/or zinc oxide. Moreover, there may be small amounts of otherelements included in each target.

The angle theta (θ), between the Zr and Zn targets, as shown in FIG. 5,is from about 0 to about 60 degrees, more preferably from about 10 toabout 50 degrees, and most preferably from about 30 to about 45 degrees.This can be accomplished by leaving the Zr target substantiallyperpendicular to the plane of the substrate 1, and tilting the Zn targetsuch that the angle between the two targets is theta (θ), as shown inFIG. 5. In certain example embodiments the aforesaid ranges result in agood overlap of Zn and Zr particles in layer 3, which in turn forms awell-mixed zirconium oxide matrix in which zinc oxide is “hidden.”

In a second example embodiment, the coating is deposited via powercontrolled co-sputtering. In this embodiment, the Zr and Zn targets mayor may not be substantially parallel, and are sputtered using differentpowers to control the composition and crystallinity of the layer 3 in adesirable manner.

For example, in certain non-limiting embodiments, in depositing layer 3the power used with the Zn target is from about 0.6 to 4.6 kW, morepreferably from about 1.6 to 3.6 kW, most preferably from about 2.1 to3.1 kW, with an example value of 1.6 kW. For the Zr target, the powerused in depositing layer 3 can be from about 0.5 to 4.5 kW, preferablyfrom about 1.5 to 3.5 kW, more preferably from about 2.0 to 3.0 kW, withan example value of 1.5 kW. The power of each target may besubstantially constant throughout deposition, or may be varied.

In a third example embodiment, one target used in depositing layer 3 maycomprise zirconium and zinc (and possibly oxides of each) in a certainratio that operates to help control the composition and crystallinity ofthe layer 3. For example, the target may contain a patched pattern ofzirconium and zinc to ensure that each respective element is depositedin the desired amount, and is in substantially crystalline form (or in aformation that is conducive to becoming crystalline upon heattreatment). The target may also comprise any pattern that would createthe appropriate ratio and structure when sputtered. The first, second,and third embodiments described herein may or may not be used incombination with each other.

Another example embodiment includes sequential sputtering from separateZn and Zr targets. In this embodiment, thin, alternating layers ofzirconium (or zirconium oxide) and zinc (or zinc oxide) may be formed.For example, in FIG. 8a a zirconium oxide based layer 4 is sputteredfirst on the glass substrate 1. Then, in FIG. 8b a zinc oxide basedlayer 5 is sputtered second. FIG. 8c illustrates an example of thensputtering zirconium a second time to form another zirconium oxide layerover the zinc oxide layer 5. FIGS. 8a, 8b, and 8c represent discretelayers formed by sequential sputtering prior to heat treatment as anexample only; and the order in which these layers are sputtered can bealtered. In this embodiment, the discrete layers are formed prior tothermal tempering. It is possible that the zinc can be sputtered firstin other example embodiments. During thermal tempering, there can bemigration or diffusion between the layers of the FIG. 8a-8c embodiment.With the approach described herein, it is possible that interdiffusionbetween discrete layers 4, 5 during tempering/heat treatment can resultin a coating with the desired antimicrobial properties. Following HT forexample, a layer comprising zinc zirconium oxide may result, asdescribed above with respect to any of the other embodiments herein.

In certain example embodiments, disposing or depositing a mixed layer ofZn:ZrO_(x) via codeposition from two sputtering targets fixtures in sucha manner as to produce overlapping sputtering distributions mayadvantageously produce temperable coatings, for example, with goodantimicrobial and/or antifungal properties. In certain cases, after heattreatment/tempering, coatings made by this process may beneficially haveexcellent antimicrobial efficacy against both bacteria and fungi whentested in accordance with JIS Z 2801 and ASTM G21; natural, clearappearance with reduced haze, possibly also with high transmittance;improved resistance to scratching by hard objects (including, forexample, glass and/or ceramic spheres) as compared to uncoated glass;and/or improved chemical durability (e.g., against staining and/or thelike) as compared to uncoated glass.

However, it has been found that in certain example embodiments,advantageous properties substantially similar to those may be obtainedin other ways. For example, in certain cases, co-deposition of a mixedlayer comprising Zn:ZrN_(x) may also produce advantageous properties.Furthermore, deposition of at least two discrete layers (e.g., with noor substantially no mixing prior to heat treating) comprising a first(“bottom”) layer of Zn metal and/or oxide, and a second (“top”) layer ofZr metal, oxide, nitride, and/or oxynitride may produce some of theaforesaid advantageous properties as well. It has been advantageouslyfound that in both of the aforesaid example embodiments, the end-productcoating (e.g., after heat treating/tempering) may perform similarly tocoatings produced by co-sputtering a layer comprising Zn:ZrO_(x). Incertain example situations, this may indicate that similar compositionsmay be produced in the heating/tempering process through diffusion,oxidation, and/or the like. These example embodiments are described inmore detail below.

An example embodiment relates to the deposition of two discrete layers(e.g., with no or substantially no significant mixing prior to heating).In certain examples, a first layer of Zn, ZnN_(x) ZnO_(x), and/orZnO_(x)N_(y) may be deposited on a glass substrate (e.g., a coated oruncoated glass substrate) and a second layer comprising Zr, ZrO_(x),ZrN_(x), and/or ZrO_(x)N_(y) may be deposited on the Zn-inclusive layer.In certain examples, the first layer may advantageously be of or includeZnO_(x) and the second layer may be of or include ZrN_(x). The coatingmay or may not include other layers above, below, and/or between the Zn-and Zr-inclusive layers. After the coating is formed, the coated articlemay be tempered. In certain instances, the tempering may cause diffusionand/or oxidation, and a Zn:ZrO_(x) matrix may be formed, e.g., inconnection with a single layer produced from two discrete layers. Insome cases, the composition of a coating formed by discrete depositionmay have a similar composition to a coating made by co-sputtering.Accordingly, in certain example embodiments, an antifungal/antimicrobialcoating formed by discretely depositing the Zn and Zr based layers mayperform similarly to coatings produced by co-sputtering.

FIG. 9 illustrates a scenario in which Zn- and Zr-inclusive layers areinitially formed discretely, but ultimately result in a combined singlelayer after heat treatment in accordance with certain exampleembodiments. The coated article may include a glass substrate 1, anoptional barrier layer 2 (which may by a silicon-inclusive layer suchas, for example, a layer comprising SiOx, SixNy, SiOxNy, etc., incertain examples), and discrete layers 3 a and 3 b, which are theprecursor to layer 3 as shown, for example, in FIG. 1. In some cases,optional layer 2 may be from about 10 to 20,000 Å thick, more preferablyfrom about 50 to 10,000 Å thick, and most preferably from about 100 to1,000 Å in thickness.

Discrete layer 3 a is deposited over the glass substrate (and optionalbarrier layer 2, when layer 2 is present). Discrete layer 3 a maycomprise or consist essentially of Zn, ZnN_(x), ZnO_(x), and/orZnO_(x)N_(y) in certain example embodiments. In certain cases, whenlayer 3 a comprises ZnO_(x), x may be less than 1 or 2. In other words,layer 3 a may comprise or consist essentially of Zn, zinc nitride, zincoxynitride, and/or a sub-oxide of Zn in certain exemplary embodiments.In some cases, layer 3 a may have a thickness of from about 1 to 500 Å,more preferably from about 10 to 100 Å, and most preferably from about20 to 50 Å.

Discrete layer 3 b may be deposited over layer 3 a in some embodiments.Layer 3 b may comprise or consist essentially of Zr, ZrN_(x), ZrO_(x),ZrO_(x)N_(y) and/or according to different example embodiments. Incertain cases, layer 3 b may have a thickness of from about 10 to 2,500Å, more preferably from about 50 to 150 Å, and most preferably fromabout 100 to 250 Å.

In certain example embodiments, the coating may further comprise aprotective overcoat (layer 6). In some instances, the protectiveovercoat may be of or include diamond-like carbon (DLC). In certainexamples, the optional protective overcoat may have a thickness of fromabout 1 to 1000 Å, more preferably from about 10 to 200 Å, and mostpreferably from about 20 to 100 Å. A layer comprising DLC may bedisposed (e.g., as an outermost layer) before or after heat treating incertain example embodiments.

FIG. 9 as described above illustrates an example composition of anantimicrobial/antifungal coating prior to tempering and/or heattreatment. In certain example embodiments, after tempering and/orheat-treatment, the coating will no longer have the same structuredescribed in FIG. 9. In certain examples, after heating, layers 3 a and3 b may diffuse and/or oxidize to form layer 3 (e.g., from FIG. 1).

In certain example embodiments, discrete layer deposition may providemanufacturability advantages over co-deposition. In some instances,co-deposition and/or alternative co-deposition can be significantly morecomplex than discrete layer deposition. For example, multiple targetsmay need to be installed in the same deposition bay such that theirsputtering fluxes overlap. In some situations, the ability to do thismay be limited by available space. Thus, in some cases, co-depositionmay require more complex equipment and/or more space. Furthermore, incertain cases, there may be interactions between the targets in closeproximity when they have differing compositions. In some cases, thoseinteractions may not be desirable. Additionally, common reactive gasloading may make independent control of each target difficult.Accordingly, it has been found that in certain example embodiments, itmay be advantageous to deposit the layers discretely rather than at thesame time. However, in other embodiments, the layers may beco-deposited.

Again, in any of the above embodiments, metal or ceramic targets can beused. The targets may be planar targets or rotating cylindricalmagnetron sputtering targets, or a combination thereof.

The deposition method of zinc zirconium oxide is not limited to theabove embodiments. Any deposition method may be used that results in theappropriate structure and composition of the zinc zirconium oxide-basedlayer.

The ratio of zirconium to zinc (not including any oxygen that may bepresent) in the layer comprising zinc zirconium oxide in any exampleembodiment of this invention can be from about 2.5 to 200 in exampleembodiments, more preferably about 3.33 to 100, and most preferably fromabout 6.67 to 50. Deposition may take place in the presence of oxygen,argon, and/or other gases. The oxygen flow rate used insputter-depositing the zinc oxide and/or zirconium oxide may be betweenabout 8 and about 28 sccm in certain example embodiments; morepreferably from about 13 to 23 sccm; and most preferably from about 16to 21 sccm. If argon is present, the argon flow rate used insputter-depositing the zinc oxide and/or zirconium oxide may be fromabout 10 to 200 sccm, more preferably from about 25 to 175 sccm, andmost preferably from about 50 to 150 sccm. However, the composition ofeach layer may depend on power in addition to oxygen flow rate, in somecases. It is noted that although zirconium oxide and zinc oxide may beexpressed as ZrO₂ and ZnO respectively, and the layer formed may beexpressed as being of or comprising Zn_(x)Zr_(y)O_(z), the layer and/orcoating is not necessarily fully oxidized and stoichiometric. Partialoxidation and full oxidation of this layer and/or coating are possible.More or less oxygen will be present in the layer depending on severalfactors, including the oxygen flow rate during deposition.

The layer formed may have the formula zinc zirconium oxide. Beforeand/or after heat treatment, in the layer comprising zinc zirconiumoxide the zinc may constitute from about 0.25% to 15% (atomic) of thelayer, more preferably from about 0.5% to 10%, and most preferably fromabout 1% to 8% of the layer. Before and/of after HT, the zirconium mayconstitute from about 20% to about 50% (atomic) of the layer comprisingzinc zirconium oxide, more preferably about 25% to 45%, and mostpreferably from about 30% to 40% of the layer. Before and/or after HT,the oxygen may constitute from about 40% to 80% (atomic) of the layercomprising zinc zirconium oxide, more preferably from about 50% to 70%of the layer, and most preferably from about 55% to about 65% of thelayer. These ranges are advantageous because, for example and withoutlimitation, if the zinc concentration is too low, there will beinsufficient zinc at the surface to adequately inhibit fungal and/orbacterial growth, and if the zinc concentration is too high, thechemical stability and environmental durability of the coating willdegrade.

EXAMPLES

Table 2 illustrates the results of several example coatings that weretested for their antimicrobial activity against E. coli, as well as forscratch resistance. Table 2 indicates that there may be a connectionbetween improved antimicrobial activity and improved scratch resistance.

TABLE 2 Escherichia coli CFU Average Average (colony forming units) CFU% Antimicrobial Scratch Example a b c recovered reduction activityResistance 1 3.46 × 10⁶ 4.02 × 10⁶ 3.70 × 10⁶ 3.73 × 10⁶ N/A N/A 0.2 2<10 <10 <10 <10 >99.99 5.57 9.0, 21.0 3 <10 <10 <10 <10 >99.99 5.57 12.14 1.17 × 10³ 2.05 × 10² 3.63 × 10² 5.79 × 10² 99.98 3.81 5.7 5 5.49 ×10³ 2.63 × 10³ 8.63 × 10³ 5.58 × 10³ 99.95 2.83 1.5

The antimicrobial test results illustrated in Table 2 were carried outfollowing the Japanese Industrial Standard Test for AntimicrobialActivity and Efficacy in Antimicrobial Products (JIS Z 2801) procedure.This procedure is designed to quantitatively evaluate the antimicrobialeffectiveness of agent(s) incorporated or bound into or ontosubstantially flat (e.g., two-dimensional) hydrophobic or polymericsurfaces. The test organism was Escherichia coli ATCC 8739 (E. coli).The sample size was approximately 2″ by 2″. The inoculum volume wasapproximately 0.40 mL, and the recovery media was trypticase soy agar.

The glass samples (e.g., Examples 1-5) were inoculated with 0.4 mL of a0.2% nutrient broth with a standardized culture of the test organism.The bacterial resistance was tested against Escherichia coli and testedin triplicate. The inoculated samples were covered with an inert filmand incubated at 35+/−2° C. in a humidity chamber for 24 hours. Theuntreated sample, Example 1, was designated as a control to recoverviable cell counts immediately after inoculation. Survivingmicroorganisms were recovered via elution of the broth inoculum from thetest sample into neutralizing broth, and the number of them wasdetermined using serial dilution method.

The CFU of E. coli were determined using triplicate samples, a, b, andc. Table 2 illustrates the antimicrobial activity results after 24hours. Example 1, the control sample, was tested at both T=0 and T=24.At T=0, the average amount of viable bacteria was 2.31×10⁵ CFU.

The “Average Percent Reduction” shown in Table 2 was calculatedaccording to the following formula:

${{Average}\mspace{14mu}{Percent}\mspace{14mu}{Reduction}} = \frac{\begin{matrix}{{{{Avg}.\mspace{14mu}{viable}}\mspace{14mu}{bacteria}\mspace{14mu}{in}\mspace{14mu}{Example}\mspace{14mu}{1\mspace{14mu}@\mspace{14mu} T}} = {24\text{-}}} \\{{{{Avg}.\mspace{14mu}{viable}}\mspace{14mu}{bacteria}\mspace{14mu}{in}\mspace{14mu}{Example}\mspace{14mu}{X\mspace{14mu}@\mspace{14mu} T}} = 24}\end{matrix}}{{{{Avg}.\mspace{14mu}{viable}}\mspace{14mu}{bacteria}\mspace{14mu}{in}\mspace{14mu}{Example}\mspace{14mu}{1\mspace{11mu}@\mspace{14mu} T}} = 24}$

The Antimicrobial Activity was calculated according to the formula:Antimicrobial Activity=[log B/C], where

B=Number of viable bacteria at T=0 on untreated sample (control-Example1)

C=Number of viable bacteria at 24 hours on each Example

Overall, Examples 2 and 3 were found to have significant antimicrobialactivity against Escherichia coli bacteria in the JIS Z 2801:2000 test.Examples 4 and 5 were found to have some antimicrobial activity againstEscherichia coli. Example 1, the untreated glass substrate used as acontrol, did not show any antimicrobial activity against the organism.

TABLE 3 Ex. Flow/Power Si3N4 ZnZrNx Zn ZrNy N 1 N/A N/A N/A N/A N/A 2 40 Å 150 Å N/A N/A 15 sccm N2 0.19 kW(Zn)  1.5 kW(Zr) 3 1500 Å N/A 40 Å120 Å 30N₂, 2 kW 4 1500 Å N/A 20 Å 120 Å 30N₂, 2 kW 5 1500 Å N/A 20 Å120 Å 15N₂, 2 kW

Table 3 describes the composition of the Example coatings, and someprocess conditions under which they were formed. Example 1 was anuncoated glass substrate (e.g., the control), and Example 2 comprised aco-deposited ZnZr-based layer. Examples 3-5 each comprised two discretelayers of Zn and Zr, respectively.

Example 2, as seen above, comprised a layer formed via co-depositionwith nitrogen. Example 3, on the other hand, involved depositing azinc-based layer and then a zirconium nitride-based layer. Both Example2 and Example 3 had very good results. This may indicate that in certainexample embodiments, co-sputtering and the formation of discrete layersmay be substantially equally advantageous. In view of this, in somecases it may be more desirable to form discrete layers rather thanco-sputtering the coating, as this may be more feasible commercially andmay still produce substantially similar results in terms ofantimicrobial activity against E. coli, for example.

The thicknesses of the Zn- and Zr-based layers, respectively, were thesame in Examples 4 and 5. Furthermore, the Zn- and Zr-based layers inExamples 4 and 5 were deposited with the same power. The only differencebetween the two examples was that Example 5's Zr-based layer wasdeposited with more N₂ in the atmosphere. From Examples 4 and 5, it wasfound that when the layers were deposited with process conditionsincluding 30 sccm N₂ (and 2 kW power), there were fewer CFUs than whenlayers of the exact same thicknesses were deposited with the same powerbut 15 sccm N₂. Thus, in certain example embodiments, a higher flow rateof N (e.g., more N present in the deposition chamber) may advantageouslylead to better antimicrobial properties. In certain example embodiments,depositing the ZrN_(x)-based layer in an atmosphere using a nitrogenflow rate of at least about, but more preferably greater than 15 sccm(e.g., at least about 20, or even 30 sccm N₂) may advantageously resultin a coating with better antimicrobial properties. However, in otherexamples, the layer thickness may also be a factor in achieving goodperformance.

Examples 4 and 5, in addition to illustrating the possible relationshipbetween antimicrobial properties and nitrogen flow rate, also illustratethat the ratio between Zr and Zn may have an effect on the antimicrobialproperties of a coating. Examples 4 and 5 included coatings havingthinner zinc-based layers. Examples 4 and 5 also had lower antimicrobialactivity against E. coli (e.g., there were more colony forming units onthe substrate at the end of the test than in Examples 2 and 3). Incertain example embodiments, coatings with thinner zinc-based layersthat are formed by discrete layers oxidizing and diffusing upon heatingmay still have antimicrobial properties. These antimicrobial propertiesmay not be quite as good as those when co-sputtering or discrete layerdeposition with thicker layers of zinc is used in some examples,although they still may be effective against some bacteria and fungi. Incertain cases, this may indicated that the zinc:zirconium ratio is animportant variable that impacts performance.

In certain example embodiments when the antimicrobial/antifungal coatingis formed via discrete layer deposition, the ratio of thickness of theZn-based layer to the Zr-based layer may be at least about 1:6, morepreferably at least about 1:4.8, even more preferably at least about1:4, and most preferably at least about 1:3. However, in other exampleembodiments, other thickness ratios may be used. Particularly, otherratios may be used so long as the antimicrobial activity against E. coliand/or other bacteria and/or fungi is sufficiently reduced.

Furthermore, it has advantageously been found that in certain exampleembodiments, silver, copper, and/or mixtures thereof may be added to orincluded in the zinc zirconium oxide-based layer used for bothco-sputtering and discrete layer deposition with substantially similarantimicrobial properties. For example, some of the zinc in the zinczirconium oxide-based layer may be replaced with one or more of silver,copper, titanium and/or the like. In further examples, the aforesaidmaterials may substantially replace the zinc in layer 3.

The thickness of the layer comprising zinc zirconium oxide described inthe above embodiments can be from about 10 to 1000 Å in certain exampleembodiments, more preferably from about 200 to 800 Å, most preferablyfrom about 400 to 600 Å, with an example thickness being about 550 Å inan example embodiment.

The layer described in the above embodiments is not limited to zinc,zirconium, and oxygen. Other materials may be present in this layer, andother layers may be provided over or under the zinc zirconiumoxide-based layer. However, in certain example embodiments, the layermay comprise, consist essentially of, or consist of, Zn_(x)Zr_(y)O_(z).

In certain example embodiments of this invention, a method of making acoated article is provided. A first sputtering target comprising Zr, anda second sputtering target comprising Zn are provided. A first discretelayer comprising Zn is formed on a glass substrate via the firstsputtering target. A second discrete layer comprising Zr is formed overand contacting the layer comprising Zn. The first and second discretelayers are heat treated (e.g., together at substantially the same time)to produce a single layer comprising Zn_(x)Zr_(y)O_(z).

In addition to the features of the previous paragraph, the first layermay comprise ZnO_(x) prior to heat treatment and/or the second layer maycomprise ZrN_(x) prior to heat treatment.

In addition to the features of the previous paragraph, the second layercomprising Zr may be deposited in the presence of nitrogen.

In addition to the features of the previous paragraph, a nitrogen flowrate for at least a portion of the deposition of the layer comprising Zrmay be at least about 15 sccm, more preferably at least about 30 sccm.

In addition to the features of the paragraph four above this paragraph,in certain example embodiments, the first layer may comprise ZnO_(x) andthe second layer may comprise ZrNy prior to heat treatment.

In addition to the features of any one of the five preceding paragraphs,a ratio of a thickness of the Zn-based layer to that of the Zr-basedlayer may be at least about 1:6, more preferably at least about 1:4.

In addition to the features of any one of the six preceding paragraphs,an antimicrobial activity of the coated article (where antimicrobialactivity=[log B/C], where B=number of viable bacteria at T=0 on anuncoated substrate and C=number of viable bacteria at T=24 hours on thecoated article) may be at least about 2, more preferably at least about3, and still more preferably at least about 5.

In addition to the features of any one of the seven precedingparagraphs, the first target may be located or housed in a firstdeposition chamber and the second target may be located or housed in asecond deposition chamber.

In certain example embodiments of this invention, a method of making acoated article is provided. A first sputtering target comprising Zr anda second sputtering target comprising Zn are provided. At least thefirst and second sputtering targets are co-sputtered in the presence ofnitrogen to form a layer comprising Zn_(x)Zr_(y)N_(z) on a glasssubstrate. The layer comprising Zn_(x)Zr_(y)N_(z) is heat treatable suchthat, when heat treated, the layer comprising Zn_(x)Zr_(y)N_(z) forms alayer comprising Zn_(x)Zr_(y)O_(z) having antimicrobial and/orantifungal properties. In certain example embodiments, after heating,the layer comprising Zn_(x)Zr_(y)O_(z) may further comprise nitrogen.

In addition to the features of the previous paragraph, the layercomprising Zn_(x)Zr_(y)N_(z) may be heat treated to form a layercomprising Zn_(x)Zr_(y)O_(z) including from about 0.5% to 10% (atomic)Zn, from about 25% to 45% (atomic) Zr, and from about 50% to 70%(atomic) O; more preferably including from about 1% to 8% (atomic) Zn,from about 30% to 40% (atomic) Zr, and from about 55% to 65% (atomic) Oafter thermal tempering.

In addition to the features of the previous paragraph, an antimicrobialactivity of the coated article (where antimicrobial activity=[log B/C],where B=number of viable bacteria at T=0 on an uncoated substrate andC=number of viable bacteria at T=24 hours on the coated article) may beat least about 5.

In addition to the features of either of the two previous paragraphs,the first layer may comprise ZnO_(x).

In addition to the features of any one of the three previous paragraphs,a flow rate of nitrogen during at least part of the deposition of thelayer comprising Zr may be at least about 15 sccm

In certain example embodiments of this invention, a method of making acoated article is provided. A first sputtering target comprising Zn, anda second sputtering target comprising Zr are provided. Sequentiallysputtering is performed from at least the first and second sputteringtargets onto a glass substrate to form at least a first layer comprisingZn having a thickness of from about 20 to 50 Å, and a second layercomprising Zr located directly on the first layer comprising Zn andhaving a thickness of from about 100 to 250 Å. The Zr is sputtered inthe presence of nitrogen. The glass substrate is heat treatable withsaid first and second layers thereon to form a layer comprising zinczirconium oxide with antibacterial and/or antifungal properties on thecoated article.

This coating and glass making up the coated article may or may not beheat treated in certain example embodiments. The terms “heat treatment”and “heat treating” as used herein mean heating the article to atemperature sufficient to enabling thermal tempering, bending, and/orheat strengthening of the glass. This includes, for example, heating anarticle to a temperature of at least about 580 or 600 degrees C. for asufficient period to enable tempering and/or heat strengthening.

In certain example embodiments, co-sputtered zirconium and zinc oxidesresult in a zinc zirconium oxide-based layer that exhibits excellentscratch resistance, combined with antibacterial and/or antimicrobialproperties. In a simple scratch test where a ⅛″ diameter borosilicatesphere is dragged across the surface of the coated article, the loadwhich causes a visible scratch on the coated surface can be as high as10, 15 or 20 pounds. In comparison, uncoated glass fails this test atless than 0.5 pounds. The layer comprising zinc zirconium oxide can passa 10 lb., 15 lb., and/or 20 lb. scratch test with borosilicate spherewithout being scratched in certain example embodiments of thisinvention. In certain example embodiments, the scratch resistance may beincreased to a level higher than uncoated glass.

Although certain example embodiments have been described as including ananti-microbial agent (e.g., Zn, Ag, Cu, etc.) within a Zr carriermaterial, other carrier materials may be used in different embodimentsof this invention. Si, Ti, Hf, Al, and/or any other suitable carriermedium may be used in connection with different embodiments of thisinvention. In general, any one or more suitable binder materials may beused in connection with any one or more anti-microbial agents.

Although certain example embodiments have been described as includingco-sputtering from two targets, other example embodiments may includesputtering two or more materials from a mixed target. For instance,certain example embodiments may involve sputtering form a mixed metaltarget comprising Zn and Zr.

In certain example embodiments of this invention, there is provided amethod of making a coated article comprising a glass substratesupporting a coating. The coating is sputter deposited on the substrate,with the coating comprising an anti-microbial material located within acarrier material. The anti-microbial material comprises Zn, Ag, and/orCu. The carrier material comprises Zr, Si, Ti, Hf, and/or Al. Thesputter depositing is practiced by either (a) co-sputtering from two ormore targets, or (b) sputtering from a mixed metal target.

While the invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not to be limited to thedisclosed embodiment, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

What is claimed is:
 1. A method of making a coated article, the methodcomprising: having a first sputtering target comprising Zr and a secondtarget comprising Zn; co-sputtering from at least the first and secondsputtering targets to form a layer comprising Zn_(x)Zr_(y)O_(z) on aglass substrate, the layer having anti-bacterial and/or anti-microbialproperties; wherein the first and second sputtering targets are offsetfrom each other by an angle of 10-50 degrees, and wherein the firstsputtering target is substantially perpendicular to the substrate. 2.The method of claim 1, wherein the angle is 30-45 degrees.
 3. The methodof claim 1, wherein the layer comprises from about 0.25% to 15% (atomic)Zn, from about 20% to 50% (atomic) Zr, and from about 40% to 80%(atomic) O.
 4. The method of claim 1, wherein the layer comprisingZn_(x)Zr_(y)O_(z) is initially deposited in a nitrogen-inclusiveatmosphere and forms on the glass substrate as a layer comprising zinc,zirconium, and nitrogen.
 5. The method of claim 4, further comprisingheat treating the glass substrate with the layer comprising zinc,zirconium, and nitrogen thereon, the layer comprising zinc, zirconium,and nitrogen transforming into the layer comprising Zn_(x)Zr_(y)O_(z)upon heat treatment.
 6. The method of claim 5, wherein the heat treatingis thermal tempering.
 7. The method of claim 4, further comprising heattreating the layer comprising zinc, zirconium, and nitrogen to form thelayer comprising Zn_(x)Zr_(y)O_(z) with about 1% to 8% (atomic) Zn,about 30% to 40% (atomic) Zr, and about 55% to 65% (atomic) O.
 8. Themethod of claim 1, wherein different powers are applied for each of thefirst and second targets in order to control composition of the layercomprising Zn_(x)Zr_(y)O_(z), wherein the power for second target is1.6-3.6 kW and the power for the first target is 1.5-3.5 kW.
 9. A methodof making a coated article, the method comprising: having a firstsputtering target comprising Zr and a second target comprising Zn;co-sputtering from at least the first and second sputtering targets toform on a glass substrate a layer comprising zinc, zirconium, andnitrogen, the co-sputtering being performed in a nitrogen-inclusiveenvironment, the layer comprising zinc, zirconium, and nitrogen beingtransformable via heat treatment into a layer comprisingZn_(x)Zr_(y)O_(z) and having anti-bacterial and/or anti-microbialproperties; wherein the first and second sputtering targets are offsetfrom each other by an angle of 10-50 degrees, and wherein the firstsputtering target is substantially perpendicular to the substrate. 10.The method of claim 9, wherein the angle is 30-45 degrees.
 11. Themethod of claim 9, further comprising heat treating the glass substratewith the layer comprising zinc, zirconium, and nitrogen thereon.
 12. Themethod of claim 11, wherein the heat treating is thermal tempering. 13.The method of claim 11, further comprising heat treating the layercomprising zinc, zirconium, and nitrogen to form the layer comprisingZn_(x)Zr_(y)O_(z) with about 1% to 8% (atomic) Zn, about 30% to 40%(atomic) Zr, and about 55% to 65% (atomic) O.
 14. The method of claim 9,wherein different sputtering powers are applied for each of the firstand second targets in order to control composition of the layercomprising zinc, zirconium, and nitrogen, wherein the power for secondtarget is 1.6-3.6 kW and the power for the first target is 1.5-3.5 kW.15. A method of making a coated article, the method comprising: having afirst sputtering target comprising Zr and a second target comprising Zn;co-sputtering from at least the first and second sputtering targets toform on a glass substrate a layer comprising zinc, zirconium, andnitrogen, the co-sputtering being performed in a nitrogen-inclusiveenvironment, the layer comprising zinc, zirconium, and nitrogen beingtransformable via heat treatment into a layer comprisingZn_(x)Zr_(y)O_(z) and having anti-bacterial and/or anti-microbialproperties; wherein the first and second sputtering targets are offsetfrom each other by an angle of 10-50 degrees, wherein the firstsputtering target is substantially perpendicular to the substrate, andwherein different sputtering powers are applied for each of the firstand second targets in order to control composition of the layercomprising zinc, zirconium, and nitrogen, wherein the power for secondtarget is 1.6-3.6 kW and the power for the first target is 1.5-3.5 kW.16. The method of claim 15, wherein the first and second targets areoffset from one another by an angle less than 60 degrees.
 17. The methodof claim 16, wherein the first target is substantially parallel to theglass substrate.
 18. The method of claim 17, further comprising heattreating the glass substrate with the layer comprising zinc, zirconium,and nitrogen thereon.
 19. The method of claim 15, further comprisingheat treating the glass substrate with the layer comprising zinc,zirconium, and nitrogen thereon.
 20. The method of claim 19, furthercomprising heat treating the layer comprising zinc, zirconium, andnitrogen to form the layer comprising Zn_(x)Zr_(y)O_(z) with about 1% to8% (atomic) Zn, about 30% to 40% (atomic) Zr, and about 55% to 65%(atomic) O.